Eyewitnesses have said he shouted "Allahu Akbar" ("God is greatest") before the attack.

The attacker was then shot dead.

Police union representative Rocco Contento said officers shot the knifeman as he ran at them shouting: "I will kill you, I will kill you."

French TV channel BFMTV offered a conflicting report that he was on the ground suffering from cardiac arrest when he was shot by officers.

Interior Minister Gerard Collomb has said the injured are out of danger.

:: The investigation

Azimov's mother, father and a friend are reportedly being held in custody in the city of Strasbourg for questioning.

The friend's address was raided on Sunday and a man was arrested and led out of the home in handcuffs.

His face was hidden by a hood but he was wearing black T-shirt with "Grozny", the capital of Chechnya, on the front and a drawing of a Kalashnikov rifle on the back.

Image:Emergency services descended on the scene after the knife attack

:: Islamic State

Islamic State has said it is behind the attack, calling the knifeman one of its "soldiers".

The group's Aamaq news agency said the attack was carried out in response to the Islamic State's calls for supporters to target members of the US-led military coalition that has been battling the extremists in Iraq and Syria.

Aamaq has not provided evidence for its claim.

France's military has been active in the coalition since 2014.

:: The response

The French interior minister is to hold an emergency security meeting.

French President Emmanuel Macron said France has "once again paid the price of blood" but "will not yield an inch to the enemies of freedom".